(cokada/iStock/Getty Images) Alien megastructures built to harvest stellar energy or alter the orbits of stars may be physically feasible, according to a new analysis – satisfying both our sci-fi ...

If you’re trying to come up with the best game plan for proving the existence of extraterrestrials, you’ve got plenty of options. Naturally, you want a strategy with a high chance of success, simply ...

From the longest tunnel of the ancient world to a highway suspended above raging waters, Rome built engineering marvels that still defy belief. Explore three forgotten megaprojects that showcase the ...